Over the past twenty-three years many techniques have been developed and tested in the PCRC. The Core Protocol provides a format and process for admission and management of PCRC patients. This process of patient admission and study is a central component of Center operations upon which the PCRC's ability to support multiple research studies is based. Protocol 75-2 has the only days recorded here. It includes admissions early in pregnancy for diabetics who participate in research later in gestation. Also included are outpatient metabolic profiles for diabetic patients.